The invention relates to arrangements including a volatile coolant for automatically regulating the temperature of a casting mold.
In one advantageous arrangement of this type, a conduit extending through the wall of the casting mold for conveying a volatile coolant therethrough is connected in parallel to a cooling circuit including a condenser, which removes heat from the mold during the casting operation, and a separate heating circuit which is connected in parallel to the cooling circuit. A pump associated with the heating circuit circulates the volatile fluid through the mold, and a suitable temperature sensing element in the mold wall regulates the thermal output of the heating element, and thus the fluid temperature in the associated portion of the conduit when the temperature in the mold varies outside of predetermined limits.
Generally, the condenser in the cooling circuit is so situated that the portion of the volatile fluid in the mold proper is maintained in the liquid phase having a fixed boiling point.
One disadvantage of such arrangement is that the parallel association of the heating and cooling circuits results in a complicated and expensive construction. In addition, flexibility in the degree of cooling of the mold is quite limited in such arrangement because of the essentially fixed boiling point of the volatile liquid.